A device of the type in question is known from EP 0 649 455. The reference discloses a plurality of embodiments, among which the embodiment according to FIG. 10 is commented on.
In this embodiment a vertical portion of the rising-pipe bend projects into the collecting main from above. The lower end of this portion has provided thereon a water seal, by means of which said portion is sealed off from an immersion pipe extending vertically below the rising-pipe bend in a vertically adjustable manner. Within the rising-pipe bend, trickling water is supplied, which is intended to cool down the gas and which is finally collected in the collecting main sump. Above the water labyrinth seal, water nozzles are provided, so as to keep the water level high within the water labyrinth seal and cause the above-mentioned sealing effect.
The water labyrinth seal is open at the top, whereby contaminations may accumulate therein, which may impede the flow of water and deteriorate the flushing effect of the water labyrinth seal.
The immersion pipe projects at the lower end thereof at least partially into the collecting main sump.
The gas pressure is to be regulated by raising and lowering the immersion pipe.
Immersing the immersion pipe into the collecting main is, however, disadvantageous, since condensates and solid matter normally accumulate in a non-uniform manner in the collecting main, whereby different water levels may be caused. The immersion pipe will be contaminated when it comes into contact with the condensates. Non-uniform accumulations in the collecting main and the lifting movement of the device may cause waves on the water surface, which have a negative influence on pressure regulation.
The water level in the collecting main can only be determined theoretically, the actual water level is unknown and would have to be determined by additional measurements. The extension of the rising-pipe bend and the immersion pipe located therebelow lead to an undesirable total height and an additional load, which cannot be accepted in existing coke oven batteries.
The operating device for the immersion pipe can be arranged laterally, above or below. In so doing, the collecting main wall is penetrated, and separate sealing is necessary.
In addition, the reference also discloses differently designed lower end edges of the immersion pipe, which influence the discharge of gas.
Finally, the reference also discloses various embodiments of immersion cups having outflow openings e.g. in the area of the cup bottom. These outflow openings are disadvantageous, since they tend to clog due to the contaminations contained in the water. In order to restore the function these immersion cups must be cleaned periodically, e.g. by flushing, tipping of the cup or tilting and the use of a cleaning mandrel.